// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/sys_info.h"

#include <stddef.h>
#include <stdint.h>
#include <sys/param.h>
#include <sys/shm.h>
#include <sys/sysctl.h>

#include "base/logging.h"
#include "base/macros.h"

namespace {

int64_t AmountOfMemory(int pages_name)
{
    long pages = sysconf(pages_name);
    long page_size = sysconf(_SC_PAGESIZE);
    if (pages == -1 || page_size == -1) {
        NOTREACHED();
        return 0;
    }
    return static_cast<int64_t>(pages) * page_size;
}

} // namespace

namespace base {

// static
int SysInfo::NumberOfProcessors()
{
    int mib[] = { CTL_HW, HW_NCPU };
    int ncpu;
    size_t size = sizeof(ncpu);
    if (sysctl(mib, arraysize(mib), &ncpu, &size, NULL, 0) < 0) {
        NOTREACHED();
        return 1;
    }
    return ncpu;
}

// static
int64_t SysInfo::AmountOfPhysicalMemory()
{
    return AmountOfMemory(_SC_PHYS_PAGES);
}

// static
int64_t SysInfo::AmountOfAvailablePhysicalMemory()
{
    return AmountOfMemory(_SC_AVPHYS_PAGES);
}

// static
uint64_t SysInfo::MaxSharedMemorySize()
{
    int mib[] = { CTL_KERN, KERN_SHMINFO, KERN_SHMINFO_SHMMAX };
    size_t limit;
    size_t size = sizeof(limit);
    if (sysctl(mib, arraysize(mib), &limit, &size, NULL, 0) < 0) {
        NOTREACHED();
        return 0;
    }
    return static_cast<uint64_t>(limit);
}

// static
std::string SysInfo::CPUModelName()
{
    int mib[] = { CTL_HW, HW_MODEL };
    char name[256];
    size_t len = arraysize(name);
    if (sysctl(mib, arraysize(mib), name, &len, NULL, 0) < 0) {
        NOTREACHED();
        return std::string();
    }
    return name;
}

} // namespace base
